Re: [Freesurfer] discrepancy between p-values computed from t.nii and those stored in sig.nii
12 May
2011
12 May
'11
9:46 p.m.
Hi Doug,
I know I'm reviving an old question. It seems to me that the variance of the errors estimated the way you are proposing below (i.e. using the residuals provided by selxavg3-sess) is biased in the sense that the residuals are not whitened (i.e. they are not independent becasue there is a temporal correlation), and that I could make an incorrect inference because of that. Am I right? If so, could you perhaps suggest a way of correcting for that?
Thank you very much, Pablo
On Fri, Nov 12, 2010 at 11:03 AM, Douglas N Greve <greve@nmr.mgh.harvard.edu
wrote:
The residuals are not saved by default, but you can tell selxavg3-sess to save them by adding the -svres flag. By variance I mean the temporal variance of the mean waveform of the residuals. The t that you want is given by:
t = ces/sqrt(rvar * C'*inv(X'*X)*C)
where ces is the average ces over the ROI, the rvar is the variance described above, X is the design matrix, and C is the contrast matrix. Both of these are in the X.mat matrix.
doug
Pablo Polosecki wrote:
Oh, thank you. I am a little bit lost now. Could you clarify a little bit more for me? Could you tell where the residuals are stored? By variance of the residuals you mean variance across voxels in the ROI? What is the efficiency of the contrast?
On Thu, Nov 11, 2010 at 12:15 PM, Douglas N Greve < greve@nmr.mgh.harvard.edu mailto:greve@nmr.mgh.harvard.edu> wrote:
That's actually not the right way to do it either. You need to get the residuals for the ROI, average the residuals, compute the variance of the average residual. Then divide this by the efficiency for the contrast, then take the sqrt() of this number. This is the standard error of the ces. Then compute the average ces over the ROI. The t is then the average ces/standard error.
doug
Pablo Polosecki wrote:
Well, that is bad (beacuse there is a bug) and good (because now it is known) at the same time. I wanted to estimate a p-value for a group of voxels of interest for a certain contrast in my analysis. Instead of averaging the p values for these voxels, I thought it would make more sense to calculate the average t statistic for the voxels and then estimate the p-value for the group of voxels myself using tcdf function in matlab. So, I guess I need the t values for that, unless I can think of a workaround, which so far I couldn't. Best, Pablo On Thu, Nov 11, 2010 at 11:57 AM, Douglas N Greve <greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> wrote: Hi Pablo, you have found a bug in FSFAST in which the values in the t.nii file are actually the sqrt of the p-values. I have fixed it in our code base and it will be in the next version. Do you actually need the t-values? thanks! doug Pablo Polosecki wrote: I understand the X.mat contains the variable DOF which tells me the degrees of freedom for the analysis, right? In my case it is 5915. This is what I get when I load X.mat into a structure named 'x': x = DoSynth: 0 UseFloat: 0 SynthSeed: -1 flac0: [1x1 struct] runflac: [1x21 struct] X: [6048x133 double] DOF: 5915 rfm: [1x1 struct] yrun_randn: [] RescaleFactor: 5.6510 ErrCovMtx: 0 acfseg: [1x1 struct] acfsegmn: [6048x1 double] nrho1segmn: 0.1456 W: [6048x6048 double] On Thu, Nov 11, 2010 at 11:35 AM, Douglas N Greve <greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>>> wrote: what is your dof? Pablo Polosecki wrote: Oh, sure. It is: t.vol(test_voxel_number) ans = -0.6368 On Thu, Nov 11, 2010 at 10:25 AM, Douglas N Greve <greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>>>> wrote: sorry, I meant what is the actual value of the t in t.vol(test_voxel_number)? Pablo Polosecki wrote: Firstly, thank you for the quickyresponse. t.vol is the t-volume, loaded from t.nii using the MRIread function (i.e. t=MRIread('t.nii');). test_voxel_number is just some voxel of the volume that I'm using as an example in this sanity check (I set it to 4000 in the sample code but it could have been anything else). I'm using -(abs(t.vol(test_voxel_number) )) because that is how I think the p-value is calculated from the t-statistic is a 2 tailed test. (See for instance the matlab code of the built-in ttest.m function where you have p = 2 * tcdf(-abs(tval), df) with df being the degrees of freedom.) Still if I used the alternative you sugggest, without the minus sign, I get:my_pval=-log10(2*tcdf((abs(t.vol(test_voxel_number))), x.DOF))
my_pval = -0.1690 While I still have the stored p-value of stored_pval = -0.4055 Thanks again! On Thu, Nov 11, 2010 at 10:02 AM, Douglas N Greve <greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>>>>> wrote: what is t.vol(test_voxel_number)? Why do you use -(abs(t.vol(test_voxel_number))) instead of +(abs(t.vol(test_voxel_number)))? doug Pablo Polosecki wrote: Dear experts, For different reasons I found myself double checking the relationship between t-values in t.nii and p-values stored in sig.nii. If I use the following matlab code I thought that I should get the values of my_pval and stored_pval to be the same (except perhaps for the sign):cd(fullfile(basedir,session,'bold',anal,contrast)) x=load('../X.mat') t=MRIread('t.nii'); sig=MRIread('sig.nii'); test_voxel_number=4000;
my_pval=-log10(2*tcdf(-(abs(t.vol(test_voxel_number))), x.DOF)) stored_pval=sig.vol(test_voxel_number)
However I get: stored_pval = -0.4055 my_pval = 0.2804 Am I doing something wrong here? My FreeSurfer version is 4.5 Thank you! -- Pablo Polosecki Graduate Fellow Laboratory of Neural Systems The Rockefeller University 1230 York Avenue, Box 9 New York, NY 10065
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16 May
16 May
10:38 a.m.
New subject: discrepancy between p-values computed from t.nii and those stored in sig.nii
Those residuals are actually whitened, but there is still a problem in that you need to include the whitening matrix in the equation for the t ratio below. I don't know any easy way to do it from there. You can save the unwhitened residuals with -svres-unwhitenen, then compute the average of the residuals, then compute a whitening matrix (eg, assuming AR1), then recompute rvar and the t. But this is not perfect either. In reality, you should average the raw time courses and then do the whole analysis from scratch.
doug
Pablo Polosecki wrote:
Hi Doug,
I know I'm reviving an old question. It seems to me that the variance of the errors estimated the way you are proposing below (i.e. using the residuals provided by selxavg3-sess) is biased in the sense that the residuals are not whitened (i.e. they are not independent becasue there is a temporal correlation), and that I could make an incorrect inference because of that. Am I right? If so, could you perhaps suggest a way of correcting for that?
Thank you very much, Pablo
On Fri, Nov 12, 2010 at 11:03 AM, Douglas N Greve <greve@nmr.mgh.harvard.edu mailto:greve@nmr.mgh.harvard.edu> wrote:
The residuals are not saved by default, but you can tell selxavg3-sess to save them by adding the -svres flag. By variance I mean the temporal variance of the mean waveform of the residuals. The t that you want is given by: t = ces/sqrt(rvar * C'*inv(X'*X)*C) where ces is the average ces over the ROI, the rvar is the variance described above, X is the design matrix, and C is the contrast matrix. Both of these are in the X.mat matrix. doug Pablo Polosecki wrote: Oh, thank you. I am a little bit lost now. Could you clarify a little bit more for me? Could you tell where the residuals are stored? By variance of the residuals you mean variance across voxels in the ROI? What is the efficiency of the contrast? On Thu, Nov 11, 2010 at 12:15 PM, Douglas N Greve <greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> wrote: That's actually not the right way to do it either. You need to get the residuals for the ROI, average the residuals, compute the variance of the average residual. Then divide this by the efficiency for the contrast, then take the sqrt() of this number. This is the standard error of the ces. Then compute the average ces over the ROI. The t is then the average ces/standard error. doug Pablo Polosecki wrote: Well, that is bad (beacuse there is a bug) and good (because now it is known) at the same time. I wanted to estimate a p-value for a group of voxels of interest for a certain contrast in my analysis. Instead of averaging the p values for these voxels, I thought it would make more sense to calculate the average t statistic for the voxels and then estimate the p-value for the group of voxels myself using tcdf function in matlab. So, I guess I need the t values for that, unless I can think of a workaround, which so far I couldn't. Best, Pablo On Thu, Nov 11, 2010 at 11:57 AM, Douglas N Greve <greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>>> wrote: Hi Pablo, you have found a bug in FSFAST in which the values in the t.nii file are actually the sqrt of the p-values. I have fixed it in our code base and it will be in the next version. Do you actually need the t-values? thanks! doug Pablo Polosecki wrote: I understand the X.mat contains the variable DOF which tells me the degrees of freedom for the analysis, right? In my case it is 5915. This is what I get when I load X.mat into a structure named 'x': x = DoSynth: 0 UseFloat: 0 SynthSeed: -1 flac0: [1x1 struct] runflac: [1x21 struct] X: [6048x133 double] DOF: 5915 rfm: [1x1 struct] yrun_randn: [] RescaleFactor: 5.6510 ErrCovMtx: 0 acfseg: [1x1 struct] acfsegmn: [6048x1 double] nrho1segmn: 0.1456 W: [6048x6048 double] On Thu, Nov 11, 2010 at 11:35 AM, Douglas N Greve <greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>>>> wrote: what is your dof? Pablo Polosecki wrote: Oh, sure. It is: t.vol(test_voxel_number) ans = -0.6368 On Thu, Nov 11, 2010 at 10:25 AM, Douglas N Greve <greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>>>>> wrote: sorry, I meant what is the actual value of the t in t.vol(test_voxel_number)? Pablo Polosecki wrote: Firstly, thank you for the quickyresponse. t.vol is the t-volume, loaded from t.nii using the MRIread function (i.e. t=MRIread('t.nii');). test_voxel_number is just some voxel of the volume that I'm using as an example in this sanity check (I set it to 4000 in the sample code but it could have been anything else). I'm using -(abs(t.vol(test_voxel_number) )) because that is how I think the p-value is calculated from the t-statistic is a 2 tailed test. (See for instance the matlab code of the built-in ttest.m function where you have p = 2 * tcdf(-abs(tval), df) with df being the degrees of freedom.) Still if I used the alternative you sugggest, without the minus sign, I get: my_pval=-log10(2*tcdf((abs(t.vol(test_voxel_number))), x.DOF)) my_pval = -0.1690 While I still have the stored p-value of stored_pval = -0.4055 Thanks again! On Thu, Nov 11, 2010 at 10:02 AM, Douglas N Greve <greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>>>>>> wrote: what is t.vol(test_voxel_number)? Why do you use -(abs(t.vol(test_voxel_number))) instead of +(abs(t.vol(test_voxel_number)))? doug Pablo Polosecki wrote: Dear experts, For different reasons I found myself double checking the relationship between t-values in t.nii and p-values stored in sig.nii. If I use the following matlab code I thought that I should get the values of my_pval and stored_pval to be the same (except perhaps for the sign): cd(fullfile(basedir,session,'bold',anal,contrast)) x=load('../X.mat') t=MRIread('t.nii'); sig=MRIread('sig.nii'); test_voxel_number=4000; my_pval=-log10(2*tcdf(-(abs(t.vol(test_voxel_number))), x.DOF)) stored_pval=sig.vol(test_voxel_number) However I get: stored_pval = -0.4055 my_pval = 0.2804 Am I doing something wrong here? My FreeSurfer version is 4.5 Thank you! -- Pablo Polosecki Graduate Fellow Laboratory of Neural Systems The Rockefeller University 1230 York Avenue, Box 9 New York, NY 10065 ------------------------------------------------------------------------ _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu>> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu>>> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu>> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu>>>> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu>> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu>>> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu>> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu>>>>> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu>> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu>>> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu>> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu>>>> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu>> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu>>> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu>> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu> <mailto:Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu>>>>>> https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer -- Douglas N. Greve, Ph.D. MGH-NMR Center greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>>>>> Phone Number: 617-724-2358 <tel:617-724-2358> Fax: 617-726-7422 <tel:617-726-7422> Bugs: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting <http://surfer.nmr.mgh.harvard.edu/fswiki/BugReporting> <http://surfer.nmr.mgh.harvard.edu/fswiki/BugReporting> <http://surfer.nmr.mgh.harvard.edu/fswiki/BugReporting> <http://surfer.nmr.mgh.harvard.edu/fswiki/BugReporting> <http://surfer.nmr.mgh.harvard.edu/fswiki/BugReporting> <http://surfer.nmr.mgh.harvard.edu/fswiki/BugReporting> FileDrop: www.nmr.mgh.harvard.edu/facility/filedrop/index.html <http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html> <http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html> <http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html> <http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html> <http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html> <http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html> The information in this e-mail is intended only for the person to whom it is addressed. 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Greve, Ph.D. MGH-NMR Center greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>>>> Phone Number: 617-724-2358 <tel:617-724-2358> Fax: 617-726-7422 <tel:617-726-7422> Bugs: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting <http://surfer.nmr.mgh.harvard.edu/fswiki/BugReporting> <http://surfer.nmr.mgh.harvard.edu/fswiki/BugReporting> <http://surfer.nmr.mgh.harvard.edu/fswiki/BugReporting> <http://surfer.nmr.mgh.harvard.edu/fswiki/BugReporting> <http://surfer.nmr.mgh.harvard.edu/fswiki/BugReporting> FileDrop: www.nmr.mgh.harvard.edu/facility/filedrop/index.html <http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html> <http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html> <http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html> <http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html> <http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html> -- Douglas N. 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Greve, Ph.D. MGH-NMR Center greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>> Phone Number: 617-724-2358 <tel:617-724-2358> Fax: 617-726-7422 <tel:617-726-7422> Bugs: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting <http://surfer.nmr.mgh.harvard.edu/fswiki/BugReporting> <http://surfer.nmr.mgh.harvard.edu/fswiki/BugReporting> <http://surfer.nmr.mgh.harvard.edu/fswiki/BugReporting> FileDrop: www.nmr.mgh.harvard.edu/facility/filedrop/index.html <http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html> <http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html> <http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html> -- Douglas N. Greve, Ph.D. MGH-NMR Center greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> <mailto:greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> Phone Number: 617-724-2358 <tel:617-724-2358> Fax: 617-726-7422 <tel:617-726-7422> Bugs: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting <http://surfer.nmr.mgh.harvard.edu/fswiki/BugReporting> <http://surfer.nmr.mgh.harvard.edu/fswiki/BugReporting> FileDrop: www.nmr.mgh.harvard.edu/facility/filedrop/index.html <http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html> <http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html> -- Douglas N. Greve, Ph.D. MGH-NMR Center greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> Phone Number: 617-724-2358 <tel:617-724-2358> Fax: 617-726-7422 <tel:617-726-7422> Bugs: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting <http://surfer.nmr.mgh.harvard.edu/fswiki/BugReporting> FileDrop: www.nmr.mgh.harvard.edu/facility/filedrop/index.html <http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html>
--
Douglas N. Greve, Ph.D.
MGH-NMR Center
greve@nmr.mgh.harvard.edu
Phone Number: 617-724-2358
Fax: 617-726-7422
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5512
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freesurfer@nmr.mgh.harvard.edu
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participants (2)
-
Douglas N Greve -
Pablo Polosecki